I haven't read through all of this thread.
Just, in case no-one else has said it, you just can't make a real WW2 mod right now, because the editing tools don't exist.
There's no tool that lets you set up every city right where it would be nice, put in all the techs you want, add just the right improvements to each city, etc, unless you feel like playing as every civ there is with a saved-game editor, every turn, until you build up the world the way you want it. It would take you a lot of hours just to get cities in the right places.
Until we get the kind of tools we got for Civ2, I don't see how this all can really happen.
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err, just read GreyFox.
I guess so.
Please new-topic a bit of info for us on how you did it, maybe? thanks.